Necked-in container

ABSTRACT

Cans having a tubular body necked-in at one or both ends. The tubular body is side seamed and the ends are seamed to the tubular body.

United States Patent Potts Y Oct. 17,1972

[s4] NECKED-IN CONTAINER 72 Inventor: Vinson s. Potts, Cherry Hill, NJ.

[73] Assignee: Crown Cork & Seal Company, Inc., 6

Philadelphia, Pa. 22 Filed: Jan. 20, 1970 [21] Appl. No.: 4,295

[52] U.S. Cl ..220/67, 220/77 [51] Int. Cl. ..B65d 7/42 '[58] Field of Search ..220/67, 77, 97, 76

[56] References Cited UNITED STATES PATENTS 3,395,827 8/1'968 Latawiec ..220/76 3,512,676 5/1970 Dawsonetal.....;........ .220/67 2,342,109 2/1944 Atkinson ..220/77 1,542,662 6/1925 Brenzinger ..220/67 2,727,537 12/1955 Henchert ..-.....220/77 X 2,771,213 11/1956 Lewis ..220/67 X 2,814,416 11/1957 Campbell, Jr. et al ..220/77 3,349,952 10/1967 Bijvoet ..220/67 Primary Examiner-M. Henson Wood, Jr. Assistant Examiner-John J. Love A ttorney- Woodcock, Washburn, Kurtz, & Mackiewicz [57] I ABSTRACT Cans having a tubular body necked'in at one or both ends. The tubular body is side seamed and the en are seamed to the tubular body. 1

5 Claims, 14 Drawing Figures PAIENTElJncr 17 m2 saw 1 or 3 IAIENTEU B 17 I97? 7 3,698,596 sum 2 or 3 Fig.5

PATENTEDHN 17 I972 3. 698 596 sum 3 or 3 Fig v Fig,

1' NECKED-IN CONTAINER BACKGROUND or THE INVENTION This invention relates in general to necked-in containers.

This invention relates in particular to necked-in sheet metal cansin common use in various food industries including the beverage industry. It is necessary that such cans be inexpensive particularly where the cans are intended to be disposable. It is also necessary that the can provide an hermetic seal so that the contents will remain uncontaminated, and, if under pressure, will remain under pressure.

'In the prior art necked-in beverage cans, an hermetic seal has been obtained but only at a substantial cost. For example, U.S. Pat. Nos. 3,343,670 -Stephan and 3,349,956 Stephan disclose necked-in cans to facilitate packaging and stacking whichcomprise a tubular can bodyintegrally formed with one can end and having anecked-in section near the integrally formed end. Since most of the can is integrally formed, ,an hermetically sealed can is virtually assured. However, the integral formation of the tubular body and the end requires a process such as extrusion which is substantially more costly than the conventional seamed'can fabrication techniques utilized by the can industry. Similarly, U.S. Pat. No. 3,394,837 Hanson et al. discloses'a tubular can body integrally formed with one can end. Again, the hermetic sealing feature is assured but at substantial cost. Y

SUMMARY OF THE INVENTION It is one object of this invention .to provide a neckedin can at a low cost. In accordance with this object, a can and method for forming a can are, provided wherein the can comprises a side seamed tubular body portion having at least one necked-in terminal section seamed to a can end. By side seamin'g'the tubular body and seaming the end'tothebody, conventional low cost techniques may be utilized in fabricating the necked-in can. In further accordance with this .object, the maximum outside diameter of the can-end may be less than the maximum'outside diameter of the tubular can body. Accordingly, the overall diameter of the seamed end will be substantially less than the maximum outside diameter of the tubular body portion. The reduction in the total area of the end results in a substantial cost sav- It is another important object of this invention to provide an hermetically sealed can. In accordance with this object, the side seam which extends along the entire length of the tubular can body is constructed to withstand an internal pressure of at least 100 psi. This may be achieved by providing an interlocking portion substantially coextensive with a central portion of the tubular can body and a lap portion which extends along a necked-in terminal section of the can body and into the central cylindrical section. The lap portion of the seam after welding and soldering, will tolerate the inward crimping at the necked-in terminal section and still provide the desired hermetic seal.

BRIEF DESCRIPTION OF THE'DRAWINGS For a more detailed explanation of the invention and the foregoing objects as well as others, reference may be made to the following description taken in conjunction with the drawings wherein:

FIG. 1 is a vertical section of a can necked-in at both ends;

FIG. 2 is a partial enlarged vertical section of the necked-in can as indicated in FIG. 1; FIG. 3 is a partial elevational view of a can body before the can is necked-in;

FIG. 4 is a sectional view of the side seam taken along section lines 4-4 of FIG. 3; FIG. 5 is a sectional view of the interlocking portion of the side seam taken along section lines 5-5 of FIG. 1; Y 3

FIG. 6 is a partial elevational view of a can body having a modified side seam;

. FIG. 7 is a partial elevational view of a can body having a differently modified side seam;

FIG. 8 is a vertical section of a pair of cans necked-in I at onlyvone end, the uppercan shown in full and the lower can shown in section; and I FIGS. 9a 9f are a schematic representation of a process by which the cans are fabricated.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A beverage can 10 illustrated in FIG. 1 is necked-in at both ends by an abrupt and substantial inward crimping ,of a tubular'body 12 near ends 14. In accordance with conventional low-cost fabrication techniques in the can art, the tubular body portion is formed from a sheet metal blank and includes a side seam 16 joining opposite edges of the blank. Also in accordance with conventional low-cost fabrication techniques in the beverage can art, the ends 14 are initially formed separate from-the tubular body 12 and subsequently affixed thereto at double seams 18. Although the side seam 16 and the double seams 18 are utilized in accordance with conventional fabrication techniques in the can art, the side seam l6 and the ends 14 which are affixed to the tubular, body 12 by the double seams 18 are not conventional. I v

Focusing first on the double seamed ends 14 as shown in FIGSJ and 2, it will be seen that, due to the necking-in of the tubular body 12, the overall or maximum outside diameter of the ends14 after double seaming to the tubular body 12 is substantially less than the maximum outside or inside diameter of the tubular body 12. As a result, the total area of the ends 14, and,

consequently, the total amount of metal involved in fabricating the ends 14, is substantially less than with conventional ends which have an overall or maximum along a portion of the side seam 16. It will be appreciated that this inward crimping subjects that portion of the side seam 16 to substantial and acute deformation. As shown in FIG. 2, the tubular body 12 is substantially cylindrical at a central section 20 and sub- I stantially cylindrical at a terminal section 22 but substantially conical or tapered at a terminal annular section 24. As a result, the tubular body 12 as well as the side seam 16 shown in FIG. 1 is inwardly crimped or deformed through angles approximating 45 the apices of the angles lying between the tapered section 24 and the central and terminal and cylindrical sections 22.

While the deformation of a tubular can body without a side seam by a substantial inward crimping does not present any sealing problems, the bending of a tubular the blank 46 with the opposite longitudinal edges of the can body with a side seam does. The side seam l6 therefore includes certain features which assure that sealing problems will not develop. In particular, the side seam 16 includes an extended lap portion 26 near the terminal edges of the tubular body 12. As shown in FIGS. 3 and 4, the lap portion 26 which is not yet inwardly crimped includes a spot or projection weld 28, substantially centered on the lap portion-26. When the tubular body 12 is inwardly crimped, the weld 28 will lie midway along the tapered section 24 as shown in FIG. 1. It will be noted that the lap portion 26 actually extends into the central cylindrical section 20 as well as the terminal cylindrical section 22 so that the side seam 16 is only two-ply at the points of maximum deformation, that is, the points where the tubular body 12 is crimped or deformed through the 45 angles. An interlocking portion 30 of the side seam 16 which is four-ply extends along a substantial portion of the central cylindrical section 20. The interlocking portion 30 as shown in FIGS. 1 and 5 except for its somewhat abbreviated nature is substantially conventional and includes a series of inwardly projecting bumps 32 which lock the seamed edges of the tubular body 12 to one another to prevent axial slippage along the side seam 16. The entire side seam 16 including the interlocking portion 30 and the lap portion 26 is soldered to complete the hermetic seal.

FIGS. 6 and 7 disclose modifications of the lap portion 26 which relates to the location of the welds. In

FIG. 6 which shows the lap portion 26 before the tubular body 12 is inwardly crimped, there are two spot or projection welds 34. The locations of the welds 34 are important in that the tubular can body 12 when inwardly crimped will deform at the welds 34. Accordingly, the welds 34 assure a firm connection of the side seamed edges at points of maximum deformation. In FIG. 7 an elongated spot or projection weld 36 is centered on the lap portion 26 as in the case of the weld 28. However, the weld 36 is elongated so as to provide a firm fastening of the lap portion along the extent of the tapered section 24 once the tubular body 12 is inwardly crimped.

In FIG. 8, a pair of cans 40 are shown which are necked-in at only one end. The cans 40 are identical to the can 10 except that each of the cans 40 is not necked-in at a conventional double seamed end 42. Accordingly, identical numerals have been utilized to identify identical elements.

The cans 40 are stacked end to end with the end 14 resting upon theconventional end 42. It may be seen that the abrupt and substantial reduction in the diameter of the tubular body portion 12 of the upper can 40 at the end 14 permits the end 14 to mate within the conventional end 42. The side seam 16 including the lap portion 26 and an abbreviated and conventional lap portion 44 provides an hermetic seal for pressures in excess of 100 psi.

blank 46 interlocked and lapped. This step represents the initial operation in the formation of the side seam 16. The next operation in the formation of the side seam l6 and the third step in the fabrication of the necked-in can is depicted by FIG. 9c. As shown there, a pair of welding electrodes 48 are forming the welds 28, 34, or 36 of the lap portion(s) 26. In FIG. 9d, the last operation of the side seam formation and the fourth step in the fabrication of the can is depicted. This operation and step involves the soldering of the side seam by a solder roll 50 which is rotating in a direction to force the solder between the layers of the side seam 16.

When .the side seam 16 is formed, the can moves to the fifth step of the fabrication method which provides for the inward crimping of the tubular body as depicted by FIG. 9e. A mandrel 52 is inserted into the interior of the tube while a crimping tool 54 passes around the exterior of the tubular body 12. When thecrimping tool 54 has traveled a number of revolutions around the w bular body 12, the necking-in operation is completed.-

If the tubular body 12 is to be necked-in at both ends, the mandrel 52 is collapsible to permit its removal from the necked-in tubular body 12. The layers of metal at the lap portion 26 and the interlocking portion 30 of the side seam 16 have been shown as mutually spaced for purposes of illustration only. They are actually in mutual contact to provide an hermetic seal.

After the tubular can body 12 is completed by flanging both ends, the can ends 14 and 42 may be affixed. As depicted by FIG. 9f, the end 14 is double seamed to the tubular can body 12. The layers of metal at the double seam 18 have been shown as mutually spaced for purposes of illustration only.

Although the present invention has been described in connection with the details of particular cans and a method for making the cans, it is to be understood that such details are not intended to limit the following claims. Furthermore, the terms and expressions employed are used in the descriptive and not a limiting sense and there is no intent to deprive the following claims of a full breadth of equivalents.

What is claimed is:

1. A metal can comprising:

a substantially tubular can body including a substantially cylindrical central section and at least one necked-in terminal section, said necked-in terminal section having a tapering annular portion providing an abrupt and substantial reduction in diameter of said tubular can body, said tubular can body further including a side seam extending along said tubular body including said necked-in section, said side seam including a soldered interlocking portion extending along said cylindrical central section and at least one lap portion extending throughout said at least one necked-in terminal section and into said cylindrical central section,

said interlocking portion of said seam providing an hermetic seal under pressures in excess of 100 psi; and

a can end double seamed to each said at least one tion and said terminal cylindrical section, said tapering annular section extending radially outwardly beyond the adjacent can end, said side seam including a soldered interlocking portion exnecked'in terminal Section, Said can end having a 5 tending along said central section and soldered lap maximum outside diameter substantially less than portions extending f each f Said terminal the inside diameter of said cylindrical central secedges at least one f said lap portions extending Said lap Portion extendmg along the curved throughout said at least one terminal cylindrical surface of said tapering annular portion so as to ex- Section along the entire length of the curved Sup tend'substantially radially and axially beyond said to face of Said tapering annular section and into said double seamed can and P expose a central cylindrical section so as to expose a substamla] segment 9 lap F the f stantial segment of said one lap portion without sures generated l h the comamer reinforcement by a double seamed end, said segforcemem by Said Said ment being soldered to provide a substantially posed segment of said portion being soldered so as to also provide an hermetic seal under pressures in excess of l00psi.

leak-proof seal alongthe entire length of said seam.

3. The metal can of claim 2 wherein said exposed segment of said at least one of said lap portions is welded. I

4, The metal can of claim 3 wherein said at least one 2. A metal can for containing highly pressurized contents comprising: Y

a pair of can ends; and

a substantially tubular can body having spaced terthan the inside diameter of said central cylindrical section, and an abruptly inwardly tapering'annular section intermediate said central cylindrical secof said lap portions is welded at a point on said annular tapering section.

5. The metal can of claim 4 wherein said at least one of said lap portions is welded at the junction of said central cylindrical section and said annular tapering section and the junction of said terminal cylindrical section and said annular tapering section. 

1. A metal can comprising: a substantially tubular can body including a substantially cylindrical central section and at least one necked-in terminal section, said necked-in terminal section having a tapering annular portion providing an abrupt and substantial reduction in diameter of said tubular can body, said tubular can body further including a side seam extending along said tubular body including said necked-in section, said side seam including a soldered interlocking portion extending along said cylindrical central section and at least one lap portion extending throughout said at least one necked-in terminal section and into said cylindrical central section, said interlocking portion of said seam providing an hermetic seal under pressures in excess of 100 psi; and a can end double seamed to each said at least one necked-in terminal section, said can end having a maximum outside diameter substantially less than the inside diameter of said cylindrical central section, said lap portion extending along the curved surface of said tapering annular portion so as to extend substantially radially and axially beyond said double seamed can end and thereby expose a substantial segment of said lap portion to the pressures generated within the container without reinforcement by said double seamed end, said exposed segment of said portion being soldered so as to also provide an hermetic seal under pressures in excess of 100 psi.
 2. A metal can for containing highly pressurized contents comprising: a pair of can ends; and a substantially tubular can body having spaced terminal edges joined with said can ends by double seams and having a leakproof side seam extending between said terminal edges, said body comprising a cylindrical terminal section, at least one terminal cylindrical section having an outside diameter less than the inside diameter of said central cylindrical section, and an abruptly inwardly tapering annular section intermediate said central cylindrical section and said terminal cylindrical section, said tapering annular section extending radially outwardly beyond the adjacent can end, said side seam including a soldered interlocking portion extending along said central section and soldered lap portions extending from each of said terminal edges, at least one of said lap portions extending throughout said at least one terminal cylindrical section along the entire length of the curved surface of said tapering annular section and into said central cylindrical section so as to expose a substantial segment of said one lap portion without reinforcement by a double seamed end, said segment being soldered to provide a substantially leak-proof seal along the entire length of said seam.
 3. The metal can of claim 2 wherein said exposed segment of said at least one of said lap portions is welded.
 4. The metal can of claim 3 wHerein said at least one of said lap portions is welded at a point on said annular tapering section.
 5. The metal can of claim 4 wherein said at least one of said lap portions is welded at the junction of said central cylindrical section and said annular tapering section and the junction of said terminal cylindrical section and said annular tapering section. 